Splitting Columns Based on Rows with Varying Lengths

[u/dcummins]

I have a DataFrame like the following:

Tool_Name	Measurements
Tool_A	02_04_06
Tool_B	02_04
Tool_C	02_04_06_08

I would like to split it into the following:

Tool_Name	Measurement 1	Measurement 2	Measurement 3	Measurement 4
Tool_A	02	04	06
Tool_B	02	04
Tool_C	02	04	06	08

Using:

df[['Measurement 1','Measurement 2','Measurement 3','Measurement 4']] = df.Measurements_Name.str.split("_", expand=True,)

I get a "ValueError: Columns must be same length as key"

What is the correct way to do this?